This selection of portraits displays Paul's interest in nature, hunting, and fishing. He started collecting insects as a child, and his collection was considerably enhanced by his godmother, George Sand, who gave him butterflies for his birthday. As a collector, Paul joined the Entomological Society in 1891. Two cave-dwelling insects, Carabidae Pterostichus (Lianoe) Nadari and Bathyscia Nadari, later renamed Speonomus pyreneus subspecies nadari, seem to have been named after him.